On Wed, May 07, 2008 at 02:36:57PM -0700, Linus Torvalds wrote:That fix is going to be fairly difficult. I will argue impossible. First, a little background. SGI allows one large numa-link connected machine to be broken into seperate single-system images which we call partitions. XPMEM allows, at its most extreme, one process on one partition to grant access to a portion of its virtual address range to processes on another partition. Those processes can then fault pages and directly share the memory. In order to invalidate the remote page table entries, we need to message (uses XPC) to the remote side. The remote side needs to acquire the importing process's mmap_sem and call zap_page_range(). Between the messaging and the acquiring a sleeping lock, I would argue this will require sleeping locks in the path prior to the mmu_notifier invalidate_* callouts(). On a side note, we currently have XPMEM working on x86_64 SSI, and ia64 cross-partition. We are in the process of getting XPMEM working on x86_64 cross-partition in support of UV. Thanks, Robin Holt --
| Greg KH | [GIT PATCH] driver core patches against 2.6.24 |
| Tarkan Erimer | Re: Dual-Licensing Linux Kernel with GPL V2 and GPL V3 |
| Amit K. Arora | [RFC] Heads up on sys_fallocate() |
| Chuck Ebbert | Why do so many machines need "noapic"? |
git: | |
| Jarek Poplawski | [PATCH] pkt_sched: Destroy gen estimators under rtnl_lock(). |
| David Miller | [GIT]: Networking |
| Gerrit Renker | [PATCH 27/37] dccp: Integration of dynamic feature activation - part 2 (server side) |
| Natalie Protasevich | [BUG] New Kernel Bugs |
